This invention relates to an X-ray diagnostic apparatus in which an X-ray transmission image of an object, e.g., a patient, is available for diagnostic purposes, and more particularly to an X-ray diagnostic apparatus by which an X-ray transmission image of the object is obtained based upon only primary X-rays.
Description of Prior Art:
Generally, in the X-ray diagnostic apparatus set fourth in the preamble, X-rays incident on an X-ray detector contains not only primary X-rays but also scattered X-rays, which are scattered by an object to be examined, e.g., a patient. The scattered X-rays constitute one of the major causes to deteriorate contrast and resolution in the X-ray transmission image. This makes it necessary the elimination of an image component on the scattered X-rays from the X-ray transmission image data as sensed and provided by the detector.
One of the approaches to eliminate the scattered X-ray component is to use a so-called "Buckey Blend" or an elimination grid for scattered X-rays (referred to as a "grid"). This approach also involves a problem that there is a limit in the scattered X-ray elimination, because the grid per se scatters the X-rays incident thereon.
The elimination of the scattered X-rays is of significance in the field of X-ray diagnosis for the reason that it improves image quality, such as contrast and resolution, and thus it allows a logarithm conversion of the primary X-rays image data, thereby obtaining an accurate attenuation quantity of X-rays caused when the X-rays pass through the object. Many studies have been made on the scattered X-rays, aiming at their effective elimination. The complicated phenomena of the scattered X-rays impedes or almost rejects a theoretical approach to this theme. This is the present stage of technology in this field.
For the above background reason, an object of the present invention is to provide by introducing a novel technical idea an X-ray diagnostic apparatus which can effectively eliminate the scattered X-rays image component from the transmission X-ray image components as obtained by the X-ray detector.